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            <h2 class="title" style="clear: both"><a id="envStats"></a>Environment Statistics</h2>
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      <p>
        JE offers a wealth of information that you can examine regarding your environment's operations. The majority
        of this information involves numbers relevant only to the JE developer and as such a description of those
        statistics is beyond the scope of this manual.
    </p>
      <p>
        However, one statistic that is very important (especially for
        long-running applications) is 
        <code class="methodname">EnvironmentStats.getNCacheMiss()</code>. 
        This statistic returns the total number of
        requests for database objects that were not serviceable from the cache. 
        This number is important to the
        application administrator who is attempting to determine the proper size for the in-memory cache.

        See <a class="xref" href="cachesize.html" title="Sizing the Cache">Sizing the Cache</a> for details.
    </p>
      <p>
        To obtain this statistic from your environment, call <code class="methodname">Environment.getStats()</code> to return
        an <code class="classname">EnvironmentStats</code> object. You can then call the 
		<code class="methodname">EnvironmentStats.getNCacheMiss()</code> method. For example:
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      <a id="je_env5"></a>
      <pre class="programlisting">import com.sleepycat.je.Environment;

...

long cacheMisses = myEnv.getStats(null).getNCacheMiss();

...  
</pre>
      <p>
    Note that <code class="methodname">Environment.getStats()</code> can only obtain statistics from your application's
    process.  In order for the application administrator to obtain this statistic, you must either 
    use JMX to retrieve the statistic
    (see <a class="xref" href="jmx.html" title="JConsole and JMX Support">JConsole and JMX Support</a>)
    or you must print it for examination (for example, log the value once a minute).
</p>
      <p>
    Remember that what is really important for cache sizing is the change in this value over time, and not the actual value
    itself. So you might consider offering a delta from one examination of this statistic to the next (a delta of 0 is
    desired while large deltas are an indication that the cache is too small).
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